Stockholders' Equity - Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders’ equity	$ 16,441	$ 9,869	$ 5,106	$ 3,749
Unrealized gain (loss) on available-for-sale debt securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders’ equity	(7)	3
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders’ equity	(53)	(27)
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders’ equity	$ (60)	$ (24)	$ (32)	$ (36)